Any of conventionally available power-driven vehicles and machinery uses a transmission-gear-shift lever having constitution such as the one shown in FIG. 10 for example.
To make up the shift lever shown in FIG. 10, plastic sphere 102 is first secured to the external surface of relatively short metal base tube 101 which extends itself straight-forwardly, while securing plastic sphere 102 to lever retainer (not shown), lever body 103 made of solid metal is integrally connected to the upper part of said base tube 101 using welding means. Next, screw 105 is secured to the upper end of said lever body 103 for installing knob 104 to said screw 105, and then metallic tube pivot 106 is integrally connected to the bottom part of said base tube 101 by applying welding means to allow shifting rod 107 to be connected to said tube pivot 106.
However, said shift-lever manufactured by the conventional method described above is still subjected to a variety of problems to solve, which are described below.
Since lever body 103 is substantially made of solid round rod, when operating said shift-lever connected to the predetermined part of the speed-changing gear, vibration generated by engine and transmission mechanism is directly transmitted to said shift-lever, thus eventually causing said shift-lever to continuously and slightly vibrate itself.
Structurally, since main components of any conventional shift-level are comprised of three units including base tube 101, sphere 102, and the lever body 103, a large number of component parts are needed, and yet, welding process is indispensible for connecting lever body 103 to base tube 101. Conversely, the welded portion generated by said welding process easily causes its mechanical strength to lower during service life.
In addition, reflecting a large number of component parts needed, assembly and control operations involve numerous processes.
Furthermore, since the lever body 103 itself is made of solid round bar, each piece is provided with a specific weight, and as a result, light-weight construction cannot easily be realized.